GB639267A - Lathes - Google Patents

Abstract

639,267. Lathes. BARKER, R. V. Aug. 8, 1947, No. 22092. [Class 83 (iii)] A lathe has a headstock rotatable about a vertical axis relatively to the frame on which the tool saddle moves so that the axis of the rotating workpiece may be at any desired angle to the line of movement of the saddle. The latter comprises base parts 1 and 2, of the same height and machined flat, on to which are bolted head and tail brackets 3, 4, respectively. Horizontal bores are provided in these brackets, one at each of the top corners and one at the front bottom corner, to take cylindrical shafts 5, 6, and 7 (not visible in the -drawing) to provide the bed. The shaft 6 is formed underneath with work teeth 9 for feeding a tool saddle 20 which slides along the top two shafts. The saddle may, however, be omitted in the simplest form for wood-turning operations. The saddle may be provided with a tool rest 26 carried by a cross-slide movable by a handle 25 over partly cylindrical guides 104. In the simplest form the lathe may be driven by a treadle arrangement driving a spindle 10 carrying a faceplate 15 secured on a taper 12 by a bayonet-type connection 14, 17. The headstock is rotatable about a vertical axis to enable tapers to be cut and may be turned through 180 degrees where operations on large diameter work are necessary, a separate tool rest is then used. As stages in increasing the capabilities of the lathe a lead screw 38 may be secured to the bed and driven from a central shaft 42 (in the headstock) bevel gearing, and change - speed gears (not shown). The spindle may also be driven by an electric motor 28 secured to the top of the headstock driving through chain and sprocket gear a toothed wheel 32 secured to sprocket 31 but running loose on the spindle, reduction gears 33, 35 (not shown), and 36 (fixed to the spindle) complete the drive, these wheels may be changed, a slidable mounting being provided for one pair of wheels. The bevel wheel 47 may drive a fluid pump 59 (broken lines) and flexible pressure lines are then led to a cylinder 58 and ram 63 attached to the saddle. The ram 63 is provided with rack teeth to engage a pinion 64 on one of the shafts of the saddlefeed train gears. This drive may either be used to feed the saddle or it may be engaged with the cross slide to obtain a fluid-driven transverse motion. A bevel take-off drive from the shaft 42 is also described in connection with a connecting rod and slotted disc crank drive to the saddle for cutting oil grooves on cylindrical work carried by the lathe spindle. Oil grooves may also be cut on the flat face of work mounted on the spindle by a similar arrangement at right angles to that described above.